In a message dated 10/23/99 7:12:48 AM, albell@UVIC.CA writes: << >The heater core is in line with the engine, not the radiator, so it will show >the same pressure that's currently in the engine. The radiator doesn't >have any >pressure until the thermostat opens. >> This is incorrect. There is no coolant flow through the radiator until the thermostat opens but, in this closed system it certainly will be under system pressure. I feel that most of the trouble owners have with the waterboxer engine results from the cooling system not being bled (i.e., purged of air) properly. There was a posting on this forum regarding head leaks being caused by "hot spots" in the head. The remedy was to apply a ceramic coating to the combustion chamber in order to subdue the rate of heat transfer into the head. While adding this thermal interface to the heat flow path will reduce localized heating, all it does for me is to show the extremes to which some are going in order to correct a maintenance deficiency.If head leaks do occur at hot spots, nothing else will cause the head to heat up like a good old air pocket. Unfortunately, I have found the air venting procedures in the Bentley manual to be almost useless. Considering the number of Vanagons I have seen with less than full coolant pressure tanks, I wonder how many others are relying on this ineffective procedure only to blame a leaking head on a weak design. Believe me, the laws of thermodynamics were worked out long before VW put pencil to paper for the Vanagon; if the waterboxer really needed ceramic coatings, it would have had them. Rich |
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.